What do you all think is an essential parameter and it's range for intelligent life to form.

I don't know the parameter range, but you will probably need a carbon fossil-fuel phase to allow intelligence to develop. At least cooking meat over an open fire was apparently essential to allowing humans to get off of a fruit and vegetable diet, which allowed for a smaller gut so that they could walk upright (freeing their hands to use tools) and also allow for larger brain development due to more proteins in the diet. You also need enough fossil fuels for the industrial age, without which you would never get the scientific instruments necessary to explore the universe, or even your own planet. Therefore, the planet must be old enough to allow such fossil fuels to develop, and would have to have gone through various tropical/non-tropical phases to allow for both the growth of plants and their preservation for a later time.

However, you may not make it past the carbon age due to Global Warming if there are no ready substitutes, and you don't learn how to use them soon enough. So you may possibly need uranium (or thorium) to allow for a nuclear age. But the uranium must have enough U235 to allow for enrichment to useable levels. However, if there is too much U235, then it is too easy to make nuclear weapons, and the civilization probably won't make it past that phase either.

You can speculate that slugs, etc. have intelligence, but that won't get you very far. They did not develop it on our planet, due to lack of mobility, etc., and they probably won't on any other. The most likely life forms that we can know of at the moment would probably go through a phase more or less like our own, though how they develop a million years after that is another question.

The scrutinized planet, which is known as GJ1214b, is classified as a super-Earth type planet because its mass is intermediate between those of Earth and Neptune. Recent searches for planets around other stars ("exoplanets") have shown that super-Earths like GJ 1214b are among the most common type of planets in the Milky Way galaxy. Because no such planets exist in our Solar System, the physical nature of super-Earths is largely unknown.

What do you all think is an essential parameter and it's range for intelligent life to form.

I have added the existence of volcanoes to the list of essential parameters. This is the source of Carbon Dioxide which is essential to get life going on land and sea.

Then I'm thinking of the theory of life originating from the collision of 2 celestial bodies...

Not necessarily. If we use the solar system as an example then volcanoes on rocky planets would be very common. Earth has volcanoes, as did Mars and Venus has an estimated 1500 active volcanoes and there is considerable evidence that Mercury had volcanoes in the distant past.

I'd be surprised to find rocky, roughly Earth sized planets that didn't have volcanoes at least somewhere in their history.

What do you all think is an essential parameter and it's range for intelligent life to form.

I have added the existence of volcanoes to the list of essential parameters. This is the source of Carbon Dioxide which is essential to get life going on land and sea.

Then I'm thinking of the theory of life originating from the collision of 2 celestial bodies...

Not necessarily. If we use the solar system as an example then volcanoes on rocky planets would be very common. Earth has volcanoes, as did Mars and Venus has an estimated 1500 active volcanoes and there is considerable evidence that Mercury had volcanoes in the distant past.

I'd be surprised to find rocky, roughly Earth sized planets that didn't have volcanoes at least somewhere in their history.

True, but it could be not every rocky planet has a liquid and spinning core I think.rOZZMusicPictures

What do you all think is an essential parameter and it's range for intelligent life to form.

I have added the existence of volcanoes to the list of essential parameters. This is the source of Carbon Dioxide which is essential to get life going on land and sea.

Then I'm thinking of the theory of life originating from the collision of 2 celestial bodies...

Not necessarily. If we use the solar system as an example then volcanoes on rocky planets would be very common. Earth has volcanoes, as did Mars and Venus has an estimated 1500 active volcanoes and there is considerable evidence that Mercury had volcanoes in the distant past.

I'd be surprised to find rocky, roughly Earth sized planets that didn't have volcanoes at least somewhere in their history.

True, but it could be not every rocky planet has a liquid and spinning core I think.

Not all, but many probably do. Mercury and Mars both have magnetic fields (albeit weak fields) which would tend to indicate a liquid, spinning core at least sometime in the past. Though, at least in the case of Mars, it is believed that the planet has cooled to the point where the core is solid.

I would tend to think that rocky worlds roughly earth sized or larger would most likely have liquid cores unless they are very, very old and have had time to cool.

Ooh... this is a VERY interesting thread! Only just came across it! Thanks Lynn!

Have only just started looking through the previous posts and they are all really very good and extremely thought provoking! I may end up going over old ground whilst I catch up... I'll try not to, but if I do I hope people won't mind.

Twin planet potentially? (I'm a twin! It's a lot of fun!) Sorry - back to the topic...

The report says:

After spotting it, the institute wasted no time searching for emissions that could indicate the presence of ETs. So far, no emissions have been found.

Am I correct in assuming that the emissions would be things like methane, and/or pollutants similar to those we produce? And if so, which would be the biggest indicator that any suspected life was in fact intelligent (assuming SETI didn't get the opportunity to analyse data from the planetary region concerned)?

Ooh... this is a VERY interesting thread! Only just came across it! Thanks Lynn!

Have only just started looking through the previous posts and they are all really very good and extremely thought provoking! I may end up going over old ground whilst I catch up... I'll try not to, but if I do I hope people won't mind.

Twin planet potentially? (I'm a twin! It's a lot of fun!) Sorry - back to the topic...

The report says:

After spotting it, the institute wasted no time searching for emissions that could indicate the presence of ETs. So far, no emissions have been found.

Am I correct in assuming that the emissions would be things like methane, and/or pollutants similar to those we produce? And if so, which would be the biggest indicator that any suspected life was in fact intelligent (assuming SETI didn't get the opportunity to analyse data from the planetary region concerned)?

490 light-years away. I would not speculate what type of atmosphere, such a planet would have. If there is alien signal, SETI has not found one.ET Phone Home

I still stand by my previous post. NASA can't even determine for sure whether or not Mars has or did have life and I think it is preposterous for them to speculate about a planet 490 LY. distant.Bob DeWoody

My motto: Never do today what you can put off until tomorrow as it may not be required. This no longer applies in light of current events.

NASA can't even determine for sure whether or not Mars has or did have life

I believe a more correct statment would be that NASA has not yet been able to determine whether life was or is on Mars. The same logic applies to this project and most other science projects, good, definitive science often takes decades or more. I say be patient and keep looking.

I think that it maybe NASA has found one or two properties that mimic Earth. It is important to define and look for the other properties that are necessary for intelligent life to form. These may well number a dozen or more.

Hopefully in time we will be able to search for and verify more and more of these.

I wonder why we have not catalogued any planets in Alpha Centauri. At "just" 4 light years away it should be easier to get a close-up look. We all believe that most stars will have a collection of various planet types.